TTY Scrollback Buffer Size

To increase the amount of scrollback on a TTY Console you can append the fbcon=scrollback:Nk option to the kernel boot arguments, for example in

menuentry Debian { icon EFI/refind/icons/os_debian.icns loader /EFI/debian/vmlinuz initrd /EFI/debian/initrd.img options "ro quiet root=/dev/mapper/vgtWyRt3-root fbcon=scrollback:1024k" }

Or an example using efibootmgr...

efibootmgr -c -p 2 -g -L "Debian (EFI stub)" -l '\EFI\debian\vmlinuz' -u root=/dev/mapper/vgtWyRt3-root ro quiet fbcon=scrollback:1024k rootfstype=ext4 add_efi_memmap initrd=\\EFI\\debian\\initrd.img

Or in Grub for example edit and append it to the GRUB_CMDLINE_LINUX_DEFAULT= option.

GRUB_CMDLINE_LINUX_DEFAULT="quiet fbcon=scrollback:1024k"

the default is 32K, using 1024k will give you about 128 half pages of scrollback.

References:

https://wiki.archlinux.org/index.php/Scrollback_buffer